1. Field of the Invention
The subject invention relates to a composition for forming an article and more specifically to an article having improved resistance to hydrolysis.
2. Description of the Prior Art
Articles based upon polyester compositions are well known to those skilled in the art. However, these polyester compositions have internal ester linkages that are susceptible to hydrolysis. Hydrolysis is a chemical reaction in which water molecules or its ions split chemical bonds and break a substance into smaller molecules. Articles that are exposed to humid conditions have a greater likelihood of undergoing hydrolysis. Articles that undergo hydrolysis tend to degrade, which is illustrated by worsened physical properties after hydrolysis than as before hydrolysis.
The polyester compositions of the related art generally include a polyalkylene terephthalate and/or polyester thereof and various other additives, such as plasticizers, impact modifiers, lubricants, nucleating agents, epoxy components, and the like. More specifically, one related art composition includes a polyester, an impact modifier, and a compound having at least one functional group selected from the class consisting of anhydrides, epoxides, and hydroxyls. The epoxides may include epoxy formed from bisphenol A or epoxidized linseed oil. Further, the composition includes plasticizers and nucleating agents. However, the related art composition does not include the unique combination of the subject invention to provide hydrolysis resistance.
The related art compositions are characterized by one or more inadequacies. Specifically, the related art compositions are prone to hydrolysis and articles formed therefrom have physical properties that degrade unsatisfactorily when exposed to conditions favorable to hydrolysis. Accordingly, it would be advantageous to provide a composition that is based on a polyester having internal linkages that is hydrolysis-resistant.